Internal combustion engine with staged compression and expansion



Feb. 16, 1932. P. AURIOL 1,845,862

INTERNAL COMBUSTION ENGINE WITH STAGED COMPRESSION AND EXPANSION Filed June 20, 1929 2 Sheets-Sheet 1 Paul/4 20 10;

i'lio-wne Feb. 16, 1932. P. AURIOL ,8

INTERNAL COMBUSTION ENGINE WITH STAGED COMPRESSION AND EXPANSION Filed June 20. 1929 2 Sheets-$heet 2 Paul Auriol;

Alia-2 71139.

Patented Feb. 16, 1932 UNITED STATES PAUL AURIOL, F PARIS, FRANCE INTERNAL COMBUSTION ENGINE WITH STAGE!) COMPRESSION AND EXPANSION Application flied June 20, 1929, Serial No. 372,485, and in France June 26, 1928.

The present invention relates to internal combustion engines and more particularly to internal combustion engines having high pressure and low pressure c linders.

g The invention has for its 0 ject to improve the efficiency of engines of the character mentioned by providing means capable of producing high compressions and evenly distributing the total pressures, and to obtain m high angular speeds by reduced strokes withp out excluding a concentrated shape of the combustion space, which, with the high pressure compressions, lends itself to a rapid combustion of the fuel directly injected by means of a pump or other suitable devices.

It is another important object of the in vention to provide an engine of the character mentioned wherein the working phase, which may be called compound by similarity to g. the so-called steam engine, extends over a larger part of the cycle than in the single cylinder engine and ensures therefore, a steadier working.

The invention also aims to improve the as conditions of eflieiency and high angular speed by providing an engine wherein a very low rate of expansion occurs at first, which subsequently increases very rapidly up to the end of the working phase.

Other important objects and advantages of the invention will be in part obvious and in part pointed out hereinafter.

In order that the invention and its mode of operation mayl be readily understood by those skilled in t e art, I have in the accompanying drawings and in the detailed description based thereupon, set out a possible embodiment of the same.

In these drawings:

Figure 1 is a front elevation of my improved device with partial section of the cylinders;

Figure 2 is a side elevation illustrating portions thereof in cross section.

5 Referring more particularly to the drawings wherein like characters of reference will designate corresponding parts throughout, I have shown for convenience and clarity herein, but one single engine unit, it being understood that as many units as desired may be used. The engine as shown essentially comprises a piston P having its head ortion formed with a curved projection an reciprocating in a vertical low pressure cylinder, B, upon which is mounted the block of the two high pressure cylinders h and h arranged in parallel relation to each other and disposed substantially at right angles or perpendicularly to the crankshafts to be later. described. The pistons of said high premure cylinders h and h are mounted to reciprocate simultaneously but in opposite directions so that the compressing stroke ofone will correspond to the working stroke of the other, at a rate of one stroke for every two strokes of the low pressure piston P in the manner hereinafter more fully described. Each of the two high pressure cylinders h and h, communicates with the low pressure cylinderthrough ports 0 and 0 having their edges, that is, t e edges nearer to the combustion space, (positioned to correspond with and adapte to receive the curved head projection of the piston P when at half of its stroke, so that one of the ports begins to open when the other has just shut.

The drawings show the engine when the low pressure piston P is at the end of its down stroke and the two high pressure pistons p and p" are respectively at the end of the ex- 8O pansion and compression strokes. Starting from this stage, the complete cycle will be accomplished when the two high pressure pistons p and p will have simultaneously un-v dergone one stroke, and thelow pressure piston P has moved two successive strokes; the various pistons willthen have the same posi tion as on starting, except that the two high pressure pistons p and p will be in inverse. relation. The piston p of the cylinder h is then about to start for a working stroke, whereas in the other high pressure cylinder h and the low pressure cylinder B,the sweeping of the burnt gases takes place. Fresh air, delivered by a pump or other suitable means, enters through the port 0 of the cylinder B, is caused to deflect upwardly by the special shape of the piston head, and sweeps out the burnt gases escaping through the port 0' and also through the port 01 of the cylinder h. The end of the sweeping phase takes place when these ports are shut by the ascending movement of the low pressure pis-. ton P and the movement from left to right of the high pressure piston p, after which these two pistons'compress together up to the end of the stroke of the low pressure piston P and half of the stroke of the high pressure piston 39, when the latter entirely covers the port 0 and proceeds alone to compress up to the end of this stroke; at the same time, the high pressure piston p opens the port o to the burnt gases already partially expended during the first half stroke of said piston 39 and which now continues to expand at the same time in the two cylinders h" and 13 until the consequently, finished expanding at the same time in the second part of the high pressure cylinder,-and the whole of the low cylinder. r

The transfer of the air from the low pressure cylinder-to one of'the high pressure cylinders causes a state of agitation, which c0- operates with the high compression and the concentrated shape of the combustion space to ensure a rapid combustion.

The ports 0 and 0' are opened by the high pressure pistons 10 and p when at their maxioscillating movements in opposite directions, and may be advantageously supported together by the two end bearings of the inner shaft.

Manifestly, the construction shown and described is capable of considerable modification and those modifications which come within the scope of my claim, I consider within the spirit of the invention.

I claim:

An engine off'the character described comprising a low pressure cylinder, a plurality of high pressure cylinders arranged in juxtaposed relationand disposed transversely of the head of said low pressure cylinder, the head of the low pressure cylinder having means of communication opening substantially in the central portion of the high pressure cylinders, a piston reciprocatingin the low pressure cylinder and having its upper. portion projected, whereby said upper por-" tion of the piston, when at its uppermost dead point, may extend within said means of communication with the high pressure cylinders and thus eliminate detrimental space.

In witness whereof I have hereunto set my hand. *1 PAUL AURIOL.

pressure mum working speed, that is, in the best conditions to avoid wiredrawing'of the gases.

The transfer of the gases from one high pressure cylinder to the low pressure cylinder is direct, free of any obstacle, and without detrimental space. 1

The proper relation between the movements of the high pressure and low pressure ,pistons is obtained through the particular arrangement and combination of the driving shafts. Disposed in parallel relation to the crankshaft M of the low pressure pistons, is I a second crankshaft D having two roller bearing eccentric shafts E and E positioned at substantially 180 fromeach other. These two shafts areconnectedby pinion 1" and gear wheel R, the number of teeth thereof being preferably in the ratio of 1 to 2. The connecting rods of the eccentric shafts'and of the high pressure pistons are connected together by means of two working beams V and V, oscillating on the same axis XX, and having their upper and lower arms respectively fixed to concentric shafts A and A.

These two shafts have, therefore, alternate p 

